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191.
Models for integrated production and demand planning decisions can serve to improve a producer's ability to effectively match demand requirements with production capabilities. In contexts with price‐sensitive demands, economies of scale in production, and multiple capacity options, such integrated planning problems can quickly become complex. To address these complexities, this paper provides profit‐maximizing production planning models for determining optimal demand and internal production capacity levels under price‐sensitive deterministic demands, with subcontracting and overtime options. The models determine a producer's optimal price, production, inventory, subcontracting, overtime, and internal capacity levels, while accounting for production economies of scale and capacity costs through concave cost functions. We use polyhedral properties and dynamic programming techniques to provide polynomial‐time solution approaches for obtaining an optimal solution for this class of problems when the internal capacity level is time‐invariant. © 2007 Wiley Periodicals, Inc. Naval Research Logistics, 2007 相似文献
192.
许志辉 《中国人民武装警察部队学院学报》2011,27(2):59-61
针对建筑设计消防审核工作中容易出现的技术问题,从消防车道与建筑中人行通道的设置、自动喷水灭火系统末端试水装置与试水阀的设置、特殊场所快速响应喷头的选用、标准喷头的设置、自动喷水灭火系统集热板的应用、室内消火栓系统阀门的设置以及防火卷帘两侧火灾探测器组与警报装置的设置等方面解读了相关消防技术规范的规定,系统分析了建筑设计消防审核中的常见错误与问题,提出了有关技术规范规定的合理解释和使用建议。 相似文献
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针对目前虚拟人上肢可触及性检查操作烦琐、效率低的问题,提出一种RRT(Rapidly-exploring RandomTree)算法与逆向运动学算法相结合的路径规划方法,通过检测可行路径是否存在来实现人体上肢可触及性检查。给出了该方法的具体流程和关键问题的解决策略,并基于Jack软件进行了实例验证。 相似文献
196.
提出一种时间表的设计方案及其改进形式,讨论了它的相关性能。应用本方案,不仅可以提高排课中搜索的效率(最高可达(2n 1)/2倍),还可以满足排课过程中对时间的各种需求,具有很强的适应性和可移植性;再利用层次分析法得到各时间段的可接受度,分析了使用改进时间表的公平性,其公平性因子将得到成倍提高。 相似文献
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Blažo M. Radović 《Defense & Security Analysis》2018,34(3):211-231
ABSTRACTThe uncritical layering of western liberal defence governance norms and concepts on top of existing legacy concepts has impeded achieving coherent military capabilities and capacities when Serbia’s political and military leadership tried to reform the defence system using Western benchmarking principles and Western countries’ best practices. The process of this change has been more valuable than its actual output, as defined by increased capabilities. Such outcomes should be reflective of policy guidance, and can be thought of as closing the trinity loop of a defence planning system: plans, money and execution. This article addresses two key functional areas of the Serbian defence institution. First, it assesses the current state of defence planning to discern its strengths and weaknesses to ascertain if plans are tied to financial decision-making. Second, a full examination of current Serbian defence management is conducted to discern whether weaknesses exist that distract from producing operational capabilities. Both areas are analyzed thoroughly and some solutions for change are proposed. Also, the article analyzes the appearance of two negative phenomena in the planning process – economization and managerialism. 相似文献
199.
《防务技术》2020,16(1):150-157
A formation model of manned/unmanned aerial vehicle (MAV/UAV) collaborative combat can qualitatively and quantitatively analyze the synergistic effects. However, there is currently no effective and appropriate model construction method or theory, and research in the field of collaborative capability evaluation is basically nonexistent. According to the actual conditions of cooperative operations, a new MAV/UAV collaborative combat network model construction method based on a complex network is presented. By analyzing the characteristic parameters of the abstract network, the index system and complex network are combined. Then, a method for evaluating the synergistic effect of the cooperative combat network is developed. This method provides assistance for the verification and evaluation of MAV/UAV collaborative combat. 相似文献
200.
《防务技术》2020,16(5):1001-1018
Path planning is a key technique of autonomous navigation for robots, and the velocity field is an important part. Constructing velocity field in a complex workspace is still challenging. In this paper, an inner normal guided segmentation algorithm in a complex polygon is proposed to decompose the complex workspace in this paper. The artificial potential field model based on probability theory is then used to calculate the potential field of the decomposed workspace, and the velocity field is obtained by utilizing the potential field of this workspace. Path optimization is implemented by curve evolution, during which the internal force generated in the smoothing process of the initial path by a mean filter and the external force is obtained from the gradient of the workspace potential field. The parameter selection principle is deduced by analyzing the influence of several parameters on the path length and smoothness. Simulation results show that the designed polygon decomposition algorithm can effectively segment complex workspace and that the path optimization algorithm can shorten and smoothen paths. 相似文献